1. Field
Embodiments of the present invention generally relate to a magnetic read head for use in a hard disk drive.
2. Description of the Related Art
The heart of a computer is a magnetic disk drive which typically includes a rotating magnetic disk, a slider that has read and write heads, a suspension arm above the rotating disk and an actuator arm that swings the suspension arm to place the read and/or write heads over selected circular tracks on the rotating disk. The suspension arm biases the slider towards the surface of the disk when the disk is not rotating but, when the disk rotates, air is swirled by the rotating disk adjacent an air bearing surface (ABS) of the slider causing the slider to ride on an air bearing a slight distance from the surface of the rotating disk. When the slider rides on the air bearing, the write and read heads are employed for writing magnetic impressions to and reading magnetic signal fields from the rotating disk. The read and write heads are connected to processing circuitry that operates according to a computer program to implement the writing and reading functions.
As the areal storage density in hard disk drives (HDDs) increases, the demand for greater magnetoresistive (MR) ratio and reduction of shield to shield distance has increased. Since high enough MR using MgO barrier based magnetic tunnel junction (MTJ) has been obtained, the reduction of shield to shield distance, or read gap to increase the spatial resolution along the track and magnetic parameters such as free layer magnetostriction, anisotropy and damping constant are becoming important factors in order to meet the required high storage density.
Therefore, there is a need in the art for a magnetic head having a reduced read gap and improved magnetostriction and damping constant.